What air pressure for BFG-285-AT's...

[FFutch]

... I tried a search but didn't come up with anything. I just got my 285-75-16's last week,wondering what pressures you guys are running. Right now I've got 65 in the front and 55 rear. The sears guys put 55 in the front but they looked bulged out. I guess there is a little weight up there ... Doug

 

[MikeR]

My bfg 285/75/16, I run 62 in front and 52 in rear. With 80k miles on them I think that is the perfect pressures.



-Mike

 

[FFutch]

Thanks Mike...

... that's what I'll run in them... . Doug

 

[Shovelhead]

So Doug, you finally burned that last 1,000 miles off 'em huh.

 

[FFutch]

Not quite...

... Ed,but the Sears guy was wanting to make a sale and cut me a break. The dyno at Glen-Burnie helped though ... Doug

 

[Ramafid]

The way I determine air pressure for the tires is with some simple math. I weighed my vehicle ( should be almost the same for all) so I knew the front and rear axle weights. Empty was 4200 front and 2560 rear. The BFG's max load is 3305 lbs at 65psi. Divide the max load by the psi and you get 50. 8 lbs per lb of air. Round to 50 to be safe and divide 4200 by 50 which gets you 84 lbs. Divide 84 lbs by 2 ( two tires) and you get 42psi per tire minimum. I would run the tires at 50psi front and still have an 800 lb cushion. The front doesn't really recieve any more weight even when loaded. The front GAWR is only 5200. on the later models. Do the same for the rear and you have optimum tire pressures.

 

[TboneMan]

Originally posted by Ramafid

The way I determine air pressure for the tires is with some simple math. I weighed my vehicle ( should be almost the same for all) so I knew the front and rear axle weights. Empty was 4200 front and 2560 rear. The BFG's max load is 3305 lbs at 65psi. Divide the max load by the psi and you get 50. 8 lbs per lb of air. Round to 50 to be safe and divide 4200 by 50 which gets you 84 lbs. Divide 84 lbs by 2 ( two tires) and you get 42psi per tire minimum. I would run the tires at 50psi front and still have an 800 lb cushion. The front doesn't really recieve any more weight even when loaded. The front GAWR is only 5200. on the later models. Do the same for the rear and you have optimum tire p

ressures.

Ramafid:

This assumes that tire "strength" and inflation have a linear relationship. Do we have any tire engineers out there to confirm this? I would suspect that the relationship between PSI and load is more logarithmic. But that's a guess.

 

[PRout]

Used to run 56 frt & 54rr.



When towing, went to 58 frt, 60 rr.



Used the surface temp method. You want to feel the same temp across the tread surface.



If theyre warmer on the edges than the center, then raise the pressure, if theyre cooler on the edges, lower it.



Got 65k on the last set of bfg's and they had alot of miles left.